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arXiv · 2311.04723

Communication Complexity of Common Randomness Generation with Isotropic States

Abstract

This paper addresses the problem of generating a common random string with min-entropy k using an unlimited supply of noisy EPR pairs or quantum isotropic states, with minimal communication between Alice and Bob. The paper considers two communication models -- one-way classical communication and one-way quantum communication, and derives upper bounds on the optimal common randomness rate for both models. We show that in the case of classical communication, quantum isotropic states have no advantage over noisy classical correlation[GR16]. In the case of quantum communication, we demonstrate that the common randomness rate can be increased by using superdense coding on quantum isotropic states. We also prove an upper bound on the optimal common randomness rate achievable by using one-way quantum communication. As an application, our result yields upper bounds on the classical capacity of the noiseless quantum channel assisted by noisy entanglement[HHH+01].

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Yangjing Dong, Penghui Yao. 2023-11-08. Communication Complexity of Common Randomness Generation with Isotropic States. https://arxiv.org/abs/2311.04723

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